Cableway



T. s. MILLER.

CABLEWAY. 7 APPLICATION FILED IUNE 9, 1920.

M m 1. m m m E O H V w m A S m H s 4 T. s. MILLER CABLEWAY.

APPLICATION FILED JUNE 9, 1920.

1,438,453. Patented Dec. 12, 1922.

4 SHEETSSHEET 2- M INVENTOR.

BY I ATTORNEYS T. S. MILLER.

CABLEWAY.

APPLICATION FILED JUNE 9, 1920.

Patented Dec. 12, 1922.

4 $HEETSSHEET 3.

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CABLEWAY. APPLICATION FILED JUNE 9. 1920.

Patented Dec. 12, 1922.

INVENTOR M A TTORNEYS Patented Dec. 12, 1922.

UNITE THOMAS SPENCER MILLER, OF SOUTH ORANGE, NEW JERSEY.

CABLEVAY.

Application filed June 9, 1920. Serial No. 387,527.

T 0 alt whom it may concern Be it known that I, THoiuAs SPENCER MILLER, a citizen of the United States, and a resident of South Orange, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Cableways, of which. the following is a specification.

My invention relates broadly and generally to new and useful improvements in ap; paratus for carrying out excavating operations.

The invention consists in the novel con struction of parts and their arrangement in operative combination to be more fully described hereinafter and the novelty of which will be particularly pointed out and distinctly claimed.

My invention will best be understood by reference to the accompanying drawings, in which I have illustrated a preferred embodimentof my invention, and in which Figure l is a view in side elevation of a complete cableway embodying my invention; Figs. l and 1? are plan views of the head. tower and the tail tower, respectively; Fig. 2 is a diagrammatic view illustrating the arrangement of the principal cables and associated parts involved in the digging and conveying operations; Fig. 3 is a side elevation of a digging and conveying device comprising a carriage and a bucket; Figt is a rear elevation thereof; Fig. 5 is a plan view, partially in section, of the digging and conveying drum and the outhaul drum and the associated parts comprising the motors or engines for driving said drums; Fig. 6 is a side elevation of Fig. 5; Fig. 7 is a longitudinal section taken along the axis of the outhaul drum 4:2 in Fig. 5 and associated parts; Fig. 8 is aside view, partially in section, illustrating the arrangement of parts by which the friction or drag on the outhaul drum is increased; Fig. 9 is a plan view of themotor or engine for operating the main supporting cable, and Fig. 10 is a side elevation thereof.

Like reference characters indicate like parts in the various figures.

Referring, now, to the drawings, 1 designates a inain supporting cable attached at one end. as at 2, to a tail tower 3, the other end of the main cable passing over a sheave i on the head tower 5 and wound upon a, drum 6 which is operated by an engine, which is indicated, in general, at T in Fig. 2. The tail tower and the head tower are, or

may be, of well known construction, and

need not,therefore, be specifically described. A take-up connection 8 of well known form is preferably included in the main cable 1 at thehead tower Both the tail tower 3 and the main tower 5 are preferably arranged to be moved along suitable track rails 9.

A digging and conveying device, which I have indicated, in general, by the reference character A (see Fig. 3) comprises a carriage 10 from which is suspended an openended digging and conveying bucket 11. The carriage comprises a suitable frame 12 suspended from the main cable 1 preferably by two sets of running wheels 13 arranged in tandem, the frame being provided with separated side-plates12" between which the various wheels are mounted and within which they have their bearings. The rear end of the bucket 11 is supported from the carriage frame by a yoke member 14L positioned on a pivotl l betw'een the plates 12" and to which are attached supporting chains 15, two of which preferably are provided and attached to either side of the rear of the bucket in order to maintain the same in a substantially horizontal position. The lower ends of the respective chains, in the form here shown, are attached to shackles 16 which are, in turn, secured to straps l7 fastened on the rear end of the bucket.

A digging and conveying cable l8 is connected from the point 19 (see Figs. 1 and 2) by two bridle chains 20 directly to the front end of the bucket, and by a chain 21 passing over a sheave 22 having its bearings at 23 in the frame of the carriage 10, the end of the chain 21 being connected by a shackle 24c to the front end of the bucket, as at 25. The front and open end of the bucket 11 is preferably provided with bevelled digging teeth 26 arranged in such a way as to cause the bucketto dive into the ground when dragged 'therealong. The digging and conveying cable 18 passes overa sheave 18 at the head tower and is wound upon a flanged drum 2? (see Figs. 5 and 6) loosely mounted on a shaft 28, but prevented from longitudinal movement thereon by collars 2'? secured to the shaft immediately without the heads of the drum. The shaft 28 has its bearings at 29 in thebed frame 30 and on which the digging and outhaul motor or engine 31, and the conveying engine 32 are mounted. The conveying engine 32 is a relatively highspeed, low-power engine, while the digging engine 31 is a relatively higlrpower, lowspeed engine. The digging engine 3 through suitable connections, drives a. shaft 33 having its bearings in the bed frame and on which is secured a pinion 34, which meshes with a gear wheel 35 loosely mounted on the shaft 28 and capable of longitudinal movement thereon. The side of the gear wheel 35 toward the head of the drum 27 is provided with a clutch element consisting of an annular bevelled flange 36 which, when moved toward the drum, frictionally engages a cooperating clutch element con sisting of a bevelled fiange37 on the end of the drum and forming a friction clutch to rotate the drum withthe said gear wheel. The flange 36 formed on the gear is forced into engagement with the flange on the drum by a suitable pressure device 38 which operates in the same manner as that which will hereinafter be described in connection with the outhaul drum. The pressure device acts upon cross-key 39 extending transversely through a slot in the shaft 28, which cross-key engages a. thrust-collar 40 which, in turn, engages the hub of the gear 35 and forces the latter toward the drum, thereby bringing the flange 36 into engagement with the flange 37 of the drum. The gear 35 is normally forced away from the drum 2?, and the friction clutch thus released by means of a spring 35 which is interposed between the gear and the drum. A similar clutch is provided at the opposite end of the drum for connecting the conveying engine to and disconnecting it from the drum 27, and in general, the connections between the conveying engine and the drum are the same as those described in connection with the digging engine with the exception that the gearing reduction between the conveying engine and the drum is less than that between the digging engine and the drum.

The end of an outhaul cable 41 is wound upon an outhalul drum 42 which is preferably located adjacent the drum 27 (see Fig.

The drum 42 is mounted for free rota- 'tion on a shaft 43, which shaft has its bearings at 44 in the bed frame, and which, it will be understood, is suitably mounted on the head tower, A pinion is secured on the shaft 43 and meshes with the gear wheel 35. Suitable friction devices, which I have indicated, in general at 46 and 46 at opposite ends of "the drum are interposed between the shaft 43 and the drum '42. The friction device at one end of "the drum comprises a head 47 surrounding the shaft and having a flange 47 which is disposed opposite a corresponding flange 42 formed on the end of the d um, suitable annular friction membore '48 and 49 preferably being interposed between the flanges '42? and 47*Fand secured respectively thereto. The head 47 is provided with a recess 50 immediately surrounding the shaft within which is disposed a coil spring 51 which is seated at one end against the bottom of the recess, or, as here illustrated, a separate plate therein, the other end of the spring engaging a collar 52, which, in turn, engages and is held in position by a cover plate 53. The tension of the spring 51 is so adjusted that under normal conditions it will force the head inwardly and the members 43 and 49 into engagement with each other with sufficient force to cre ate a drag on the drum 42 of, say, five hundred pounds. T hefriction device at the op posite end of the drum comprises a stationary head 47? provided with a flange 47 00- operating with a flange 47 on the drum. Additional friction between the head 47 and the drum 42, for the purpose of creating an additional drag on the outhaul line, is produced by means which will now' be described, A cylinder 54 is screwed, or otherwise secured, as at 55, to the end of the shaft 43, the end of the cylinder being closed by a head 54. The cylinder is provided with a piston 56 which engages the inner end of a thrust-pin or rod 57 which passes through an opening 57 (indicated in dotted lines in Fig. 8) formed in the adjacent end of the shaft 43, the other end of the pin 57 engaging a thrust-key 58 which passes transversely through the shaft 43, the thrust-key being received in a slot 58 which is wider than the thrust-hey, to permit movement thereof longitudinally of the shaft. The thrust-key 58 engages the collar 52, and when moved forwardly by the pressure device, moves the said collar and further compresses the spring 51 to increase the friction between the head 47 and the drum. A fluid, such as air under pressure, is supplied to the end of the cylinder 54 by a supply pipe 59, which is connected to a horizontal pipe 60, as shown in Fig. 8, around which the end of the cylinder rotates, it being understood that the cylinder and its piston rotate with the shaft 43, upon which they are mounted. The parts projecting from the hub of the cylinder 54 adjacent the air-supply pipes are preferably protected by a hood or cover 61,

The outhaul cable 41 is preferably sup ported by a fixed suspension cable 62, which is attached at one end to the tail tower 3 and at its other end passes over a sheave 62 on the head tower, a weight 62 being secured to the end thereof to maintain the fixed cable taut. The outhaul cable is prefer ably supported from tle fired cable by hangers 63, the details of which are more fully illustrated in my ccpending applicationSerial No. 147,539. which filed in the Patent Olhce on or about February 9, 1917. The outhaul cable 41 passes over a sheave 64 on the tail tower, as shown in Fig. 1, and is connected to a bar 41* on on the carriage frame and a collar secured on the bar 41*, the arrangement being such that the spring normally tends to thrust the rod 41 forwardly, and with the drag on the outhaul line normally exerted by the spring 51 between the head 47 and the drum 43, the spring 69 is preferably somewhat compressed, so that the pin will be free within its slot with any drag on the cable from Zero up to the normal drag with the result that normally the drag on the outhaul line does not affect the latch 68. An upwardly inclined conical member 71, preferably formed of steel, is secured on the chain 21, and when the frontv end of the bucket 11 is ele vated by a drag on the chain 21, the conical member 71 is pulled upwardly between the latch 68 and a guide member 72, which is stationary on the frame of the carriage, the latch preferably being formed with a curved front, so that the conical member will be guided into position even though it be out of proper alignment. The latch 68 is there upon forced to the right, as viewed in Fig. 3, and is thrust beneath the lower face of the conical member 71 as soon as the latter reaches a position above the detent on the latch.

As heretofore stated, the end of the main cable 1 is wound at the head tower upon a drum 6 (see Figs. 9 and 10). The drum 6 is mounted upon a shaft 73 having its bear ings at 74 in a bed frame 75, the two side members of which are connected by a cross member 76. The main drum is actuated by a motor, here shown as an engine, the two cylinders of which are indicated at 77. The motor or engine drives a shaft 7 8 having its bearings in the bed frame, and on which is secured a pinion 79 meshingwith an intermediate gear 80 secured on an intermediate shaft 81. A pinion 82 is also secured on the shaft 81 and meshes with a gear 83 on the shaft 73. The gearing between the engine and the drum is a reduction gearing for the purpose of giving to the main drum great power and low speed. It will readily be understood that under operating conditions, considerable power must be applied to the main cable and the same must be kept fairly taut. At the same time, there is ordinarily very little travel of the main cable, as in ordinary excavating operations, in which the material is takennear the surface, it is only necessary to slacken the cable comparatively littleunder the conditions commonly met with, not more than five or six feet-to bring the cable from its highest to its lowest position. It is desirable, however, that this engine be independent of any other and be operated with a single lever by the operator stationed at the head tower, to the end that he may operate the main cable at any time that it is necessary to do so, whether the bucket or carriage be in operation or not.

The operation of the device embodying my invention will readily be understood from the foregoing description and is as follows:

Assuming that the carriage and bucket are above the point where an excavation is to be made, the main supporting cable is lowered by slackening off the main cable from the main cable drum 6 to bring the bucket to the ground. The carriage and bucket are hauled forwardly by the digging and conveying motor or engine 31, which is at this time geared to the drum 2? and operates through the digging and conveying cable 18. The digging and conveying enginehauls the bucket forwardly, the bevelled front of the bucket tending to cause the bucket to dive into the ground until the bucket is filled. The digging andconveying engine or motor is preferably a comparatively highpower-low-speed motor, intended to do most of the work in the heavy digging operation, and under ordinary conditioi a may exert a pulling power of say twenty thousand to twenty-two thousand pounds on the cable 18. geared to the drum 27 before the digging operation. is completed and, preferably, is connected to the drum practically simultaneously with the and conveying engine, and may exert an additional puiling power of ten thousand to twelve thousand pounds, for example, the combined power of the two engines thus performing the digging operation. As soon as the bucket is filled, the main cable is raised while the forward movement of the bucket continues. Before the bucket is raised from the ground and while digging, usually, the pull on the chain 21 draws the carria e and the forward end of the bucket together, the conical member 71 for ing the latch 68 back against the action ofthe spring 69, and when the conical member 71 drawn to the position shown in F 3, the latch is thrust beneath the same thus retaining the forward end of the bucket in-its elevated can rying position. With the bucket free from the ground. tl ere is a tendency for both of the engines connected to the bucket to run away. because the stress is largely reduced. At this juncture the digging engine is thrown out of engagement and stopped, and the bucket and carriage conveyed to the The conveying engine 32 is also d is to be dumped at 1 teen hundred or even minute, by the high- During the movethe point of excanp, the outhaul 1 under a ceieaii tension, which, at conditions, may be approxihundred pounds. This is acby wi' ne outhaul cable 4; rection that who,

cable 18 hauls ly, the outhaul in ,m 42, is geared tie drum to wind the rriction clutch between 3i and the drum 42 perium to slip, thereby creating a ned pull on the cable, while the and convey ng device is being cable. This drag suilicient to lreep the cable well above the ground, out of the mud and grit, and it is ther desirable always to keep the rope "ly tent, to the end that it not receive any violent jellS. ,ll hen the bucket has arrived at the lumping poin the tension on the outhaul line is increased by the application of air to the cylinder 54, thereby increasing the friction between the head i? and the drum Under some conlitions, this increased drag may amount to approximately two thousand pounds, which will b sufiicient to pull the latch 68 bacl: against the "force of the spring 69. The conveying engine is disconnected from the drag line an instant the drag on the outhaul line has been increased. Any pull exerted on the inhaul line after the increased drag has been placed on the outhaul line will cause the bucizet to dump, since the latch is, at this time, released, and the weight of the bucket is suii'icient to cause the bucket to descend, the same time pulling the carriage and bucket forwardly. As soon as the bucket has dumped or has begun to dump, the tension which is present on the outhaul line this time, quickly accelerates the earand bucket and t ey are returned at I h speed to the excavating point, it beins; observed that while the engine 31 is cond to the drum 21'' through a reduction it is connected to the drum 42 Q i gearing which increc es the speed of, the drum relatively to the engine 31. l Vien the bucket reaches the exca ating point, the main cable is again lowered and the cycle of operations repeated.

It will be evident to those skilled in the art that my invention overcomes the principal difficulties that are usually incident to the use of an outhaul rope, namely, that the outha rope lies in the mud or dirt dur ing the i. auling period, and as soon as the empty bucket starts on its return journey,

hauled in by the d cucviolent jerks occur, the'outhaul rope moves about colliding with the other parts of the apparatus, fouling bolts and nuts, and, in general, producing an extremely jerky operation. In accordance with my invention the outhaul rope is kept out of the dirt and mud during the inhauling period and eliminates the erky operation, which means that wear and tear of the rope is avoided. Furthermore, the drag or pull which is produced upon the outhaul rope during the inhauling period, maintains the rope fairly taut, so that when the pull is increased, the bucket is quickly accelerated on its return journey to the excavating point, time is saved and I, therefore, am enabled to increase the number of loads excavated per day.

. I claim 1. The method of operating a cableway in which a digging and conveyingdevice is moved forwardly by twoseparate motors, which consists in connecting one motor to said device for the digging operation and the other motor for the conveying operation.

The method of operating a cableway in which a digging and conveying device is moved forwardly by two separate motors, which consists in connecting both motors to said device for the digging operation and a single motor for the conveying operation.

3. The method of operating a cableway in which a digging and conveying device is moved forwardly by a high-power low-speed motor and a low-power high-speed motor, which consists in connecting the high-power low-speed motor to said device for the digging operation and connecting the lowpower high-speed motor to sa'id device for the conveying operation, and disconnecting the high-power low-speed motor during the conveying operation.

4i. The method of operating a cableway in which a digging and conveying device is moved forwardly by a high-power low-speed motor and a low-power high-speed motor, which consists in connecting both motors to said device for the digging operation and disconnecting the high-power low-speed motor during the conveying operation.

5. The method of operating a cableway in which a digging and conveying device is moved alongthe main supporting cable by two separate motors, which consists inlowering the main cable to bJing the digging and conveying device to the excavating point, connecting one motor to said device to perform the digging operation, connecting the second motor to said device to perform the conveying operation, and disconnecting the first motor during the conveying operation.

6. The method of operating a cableway in which a digging and conveying device is hauled forwardly and to which an outhaul cable is attached, which consists in maintaining said outhaul cable under tension during the forward movement of said device and increasing the tension on the outhaul cable for the purpose of dumping said device.

7. The method of operating a cableway in which a digging and conveying device is hauled forwardly, and to which an outhaul cable is attached, and in which the front end or' the digging device is held in its elevated position by a latch during the conveying operation, which consists in maintaining said outhaul cable under tension during the forward movement of said device and increasing the tensionon the outhaul cable for the purpose of dumping said device. I 8. In a cableway, a main suspended cable, a digging and conveying device adapted to traverse said cable, separate motors, and means for connecting either or both of said motors at will to said device, whereby the device may be hauled forwardly by both motors during the digging operation and by a single motor during the conveying operation.

9. In a cableway, a digging and conveying device adapted to traverse said cableway, a drum on which said cable .is wound, a relatively high-power low-speed engine, a rela tively low-power high-speed engine, and means for operatively connecting either or both of said engines at will to said drum to move forwardly said device.

10. In a cableway, a digging and conveying device adapted to travel along said cableway and comprising an open-ended digging bucket, a cable for hauling said device forwardly, a flexible connection attached to said cable and to the open end of said bucket and passing over a sheave on the carriage whereby the front end of the bucket is raised by a pull on said cable, a member on said flexible connection for locking the digging end of the bucket to the carriage, and means for releasing said member to dump the bucket.

11. In a cableway, a digging and convey ing device adapted to travel along said cablewayand comprising an open-ended digging bucket, a cable for hauling said device, a flexible connection attached to said cable and to the open end of said bucket and passing over a sheave on the carriage whereby the front end of the bucket is raised by a pull on said cable. a member for locking the digging end of the bucket to the carriage, and an outhaul cable constructed and arranged to release the lock for dumping said bucket.

12. In a cableway, a digging and conveying device adapted to travel along said cableway and comprising an open-ended digging bucket, a cable for hauling said device, a lleirible connection attached to said cable and to the open end of said bucket and passing over a sheave on the carriage whereby the front end of the bucket is raised by a pull on said cable, a latch for locking the digging end of the bucket to the carriage while said bucket is being conveyed, and an outhaul rope constructed and arranged to release the latch.

13. In a cableway, a digging and conveying device adapted to travel along said cableway and comprising a carriage and a digging bucket suspended therefrom, a cable for hauling said device, a latch for locking thedigging end of the bucket to the carriage, and an outhaul cable connected to said latch, a yielding connection being interposed between the outhaul cable and said latch.

14. In a cableway, a digging and conveying device adapted to travel along said cableway and comprising a carriage and a digging bucket suspended therefrom, a cable for hauling said device, a flexible connection attached to said cable and to the open end of said bucket and passing over a sheave on the carriage whereby the front end of the bucket is raised by a pull on said cable, a latch for locking the digging end of the bucket to the carriage, and an outhaul cable connected to said latch, a yielding connection being interposed between the outhaul cable and said latch. v

15. In a cableway, a digging and conveying device adapted to travel along said cableway and comprising a carriage and an open-ended digging bucket, a cable for hauling said device, a latch for locking the digging end oi the bucket to the carriage, an outhaul cable connected to said latch, and a lost-motion connection between the end of the outhaul cable and said latch.

65. In a cablewa a digging and conveying device adapted to travel along said cableway and comprising a carriage and an openended digging bucket, a cable for hauling said. device, a latch for locking the digging end of the bucket to the carriage, an outhaul cable connected to said latch, a yielding connection, and a lost-motion connection between the end of the outhaul cable and said latch.

- 17. In a cableway, a digging and conveying device adapted to travel along said cableway and comprising a carriage and an open-ended digging bucket, a cable for hauling said device, a flexible connection attached to said cable and to the open end of said bucket and passing over a sheave on the carriage whereby the front end of the bucket is raised by a pull on said cable, a latch for locking the digging end of the bucket to the carriage, an outhaul cable connected to said latch. and a lost-motion connection between the end of the outhaul cable and saidlatch. i

18. In a cableway, a digging and convey in device adapt d to travel along said cacleway and comprising an open-ended digging bucket, a cable for hauling said levice, latch for locking the digging end of the bucket in elevated position, an outiaul connected to said latch, a lostmotion connection between the end of the outhaul cable said latch, means for creating a pull on the outhaul cable sul'licient in amount to keep the outhaul cable out or the dirt but insuflicient to trip said latch, and means for increasing the pull to take up said lost-motion and release said latch.

in a cableway, a di ging and conveying device adapted to travel along said cableway and comprising an open-ended di sing bucl'ret, a cable for hauling said device, a latch for locking the digging end of the bucket in elevated position, an outhaul cable connected to said latch, a lost-motion connection between the end or the outhaul cable and said latch, and means for creating sufficient drag on said outhaul cable to release said latch. I

20. In a cableway, a digging and conveying device, a cable'for hauling said device forwardly, a crum on which said cable is wound, a second cable for hauling said device in opposite direction, a drum on which said second cable is wound, a motor geared to rotate the two drums and haul said cables in opposite directions, and a friction device interposed between d motor and said second drum whereby the second cable is unwound from its drum against a frictional resistance when the digging and conveying device is hauled forwardly by said first cable.

21. In a cableway, a main cable, a carriage, a bucket suspended from said carriage, a latch for holding said bucket in carrying position, a drag line for digging and conveying in one direction, an outhaul line connected to said latch, a drum for taking up the drag line, a drum upon which said outhaul line is wound, a slio connection be tween theouthaul drum and its motor, said drums both operating simultaneously and tending to wind up the lines, and means for increasing the power or the slipping connection between the outhauldrum and its motor to cause the outhaul line to release said latch.

22. In a cableway, riage, a bucket suspended from said carriage, a latch for holcing said bucket in carrying position, adrag line for digging and conveying in one direction, an outhaul line connected to said latch, lost-motion connection between said outhaul line and said latch, a drum for taking up the drag line, a drum upon which said outhaul line is wound, a slip connection between the outhaul drum a main cable, a carand its motor, said drums both operating simultaneously and tending to wind up the lines, and means for increasing the power oi the slipping connection between the outhaul drum and its motor to cause the outhaul line to release said latch.

22. In a cableway, a main cable, a carriage, a bucket suspended from said carriage, a latch for holding said bucket in carrying position, a drag line for digging and conveying in one direction, an outhaul line connected to said latch, a lost-n1otion connection between said outhaul line and said latch,'a spring constructed and arranged to force the outhaul line forwardly out of engagement with said latch, a drum for taking up the drag line, a drum upon which said outhaul line is wound, 'a slip connection between the outhaul drum and its motor, said drums both operating simultaneously and tending to wind'up the lines, and means for increasing the power of the slipping connection between the, outhaul drum and its motor to cause the outhaul line to compress said spring and release said latch.

24. In combination, a digging bucket, a cable for hauling said bucket forwardly, an outhaul cable connected to said bucket,

means for producing a pull on the outhaul,

cable during the forward movement of said bucket, and means for increasing the pull on the outhaul cable to return the bucket.

25. in combination, a digging bucket, a cable for hauling said bucket forwardly, an outhaul cable connected to said bucket, means for producmg apull on the outhaul cable sufficient in amount to maintain the outhaul cable out or" the-dirt during the forward movement of said bucket, and means for increasing the pull on the outhaul cable to return the bucket.

26. In combination, a digging bucket, 21 cable for hauling said bucket forwardly, an outhaul cable connected to said bucket, a drum on which said outhaul cable is wound, a motor for rotating-said drum, a friction device interposed between said motor and said drum, means for continuously produc ing a predetermined amount of friction in sald device, and means for increasing the amount or said friction.

27. In combination, a digging bucket, a cable for hauling said bucket forwardly, an outhaul cable connected to said bucket, drum on which said outhaul cable is wound, a motorfor rotating said drum, a friction device interposed between saidmotor and said drum, means for continuously produc ing a predetermined amount of friction in said device, and means under the control of the operator for increasing the amount of said friction.

THGMAS SPENCER MILLER. 

